Lock



April 7, 1959 R. A. CLARK LOCK Filed Aug. '29 1955 INVENTOR.

3mm aw ATTORNEYS.

United States Patent "ice LOCK Robert A. Clark, La Grange, Ill.Application August 29, 1955, Serial No. 531,162 13 Claims. (Cl. 70-214)This invention relates to locking devices, and more specifically to acombination-type lock which may be operated by means of a push button.

It is well known that combination locks are widely used in connectionwith vaults, safes, lockers and the like, partly because of the greatsecurity and protection which they olfer and further because of the factthat these locks require no keys for their operation. With the ordinarykey-operated lock, there is always the possibility that the proper keymay be misplaced, lost or stolen, and that without possession of thatkey the owner of the lock will be unable to open it, while at the sametime one who has wrongfully acquired possession of the key may operatethe lock and deprive the owner of valuable property. In addition,keyless combination locks afford substantial protection because of thelarge number of possible letter or number combinations, only one ofwhich will serve to release the mechanism of any particular lock.

Despite these advantages, combination locks have not been favored wherefrequency of use demands a lock which may be easily and quicklyoperated, or where the location of a safe, vault or the like requires alock which may be opened under poorly illuminated conditions. The amountof time necessary to manipulate the dial knob of a combination lock isfrequently considered objectionable, especially where such a lock mustbe operated at least several times each day. As a result, combinationlocks are seldom used on ordinary doors, such as the entrance doors ofhouses and apartments, or with frequently operated switches such as theignition switches of automobiles and other motor vehicles.

Therefore, one of the main objects of the present invention is toprovide a keyless combination lock which overcomes the aforementioneddisadvantages of the combination locks in present use. Another object isto provide a combination lock which is operated by means of a pushbutton, and which need not be viewed by an operator as it is beingmanipulated. A further object is to provide a push button combinationlock which may be quickly and easily operated, the push button thereofbeing guided to different selected positions by the sense of touch ofthe operator. A still further object is to provide a compact lockingmechanism which may be mounted within a doorknob and which may be simplyand quickly operated by pressing a push button to different selectedpositons.

Other objects will appear drawings, in which:

Figure 1 is a longitudinal sectional view of a doorknob equipped wtihthe locking mechanism of the present invention, and taken along linesl-1 of Figure 3; Figure 2 from the specification and .is a longitudinalsectional view similar to Figure l,

and shows the locking mechanism in a second position; Figure 3 is across sectional view of the doorknob and lock taken along lines 3-3 ofFigure 1; Figure is a cross 2,880,606 Patented Apr. 7, 1959 sectionalview taken along lines 4-4 of Figure 1; Figure 5 is another crosssectional view of the doorknob and lock, viewed along lines 5-5 ofFigure 1; and Figure 6 shows the development upon a flat surface of acylindrical cam forming a part of the present invention.

In the specific embodiment of my invention shown in the drawings, thenumeral 10 designates a doorknob having an inner chamber 11 and aforwardly extending shaft portion 12. The shaft portion of the knob hasa bore or opening 13 which extends therethrough and communicates withthe inner chamber 11 of the knob. The knob is adapted to be secured uponthe rotatable bar of a door latch (not shown) by containing an end ofthat bar within the most forward portion of bore 13. A set screw or keymay be threaded through opening 14 extending through the wall of shaft12 for firmly and tightly mounting the knob upon the connecting barcarried by the door fixture. Since the above described structure isentirely conventional, a more detailed description herein is believedunnecessary.

Within the rear portion of the longitudinally extending bore 13 is acylindrical shaft 15 which is rotatably mounted with respect to the knob10. To prevent longitudinal movement of the shaft, I provide the shaftwith a circumferential groove 16 adapted to receive a portion of rod orkey 17 which is carried by the shaft portion of the knob at right anglesto the longitudinal axis of bore 13. As shown best in Figures 1 and 2,the rear portion of the shaft is equipped with a cylindrical sleeve 18which extends forwardly within the inner chamber 11 and fits over therear of the bored shaft portion 12 of the knob. The sleeve 18 and shaft15 operate as a single member, rotatable with respect to knob 10. WhileI prefer to join the shaft 15 with sleeve 18 by any suitable means, suchas by welding, it will be apparent that these members may be formedintegrally to provide a one-piece rotatable cylinder.

As illustrated in Figure 1, a push button 19 is slidably mounted withinthe chamber 11 of the knob, and normally projects rearwardly from theknob. This button has a forwardly extending collar 20 which is adaptedto slide longitudinally over the outer surface of sleeve 18 as thebutton is pressed forwardly and released. A coil spring 21 extendsbetween the button 19 and the cylindrical shaft 15, and biases thebutton into the normal position shown in Figure 1. In addition, theouter or exposed surface of the push button is equipped with rearwardlyextending flanges or fins 22 to facilitate the manual rotation of thebutton, as will shortly be described.

Push button 19 is not only longitudinally slidable with in the chamber11, but as indicated above it is also rotatable with respect to thesleeve 18, shaft 15 and knob 10. Means are provided for integrating thelongitudinal and rotational movement of the push button and comprise acam or track on the outer cylindrical surface of the sleeve 18 and aninwardly directed pin or cam rider 24 carried by the collar 20 of thebutton. This pin rides in the groove or track and causes the button torotate as it is pushed forwardly and as it is released.

Figure 6 is a projection of the cylindrical cam upon a flat surface, andshows the track consisting essentially of the continuous series of eightintegrated U-shaped grooves extending about the peripheral surface ofsleeve 18. Each U-shaped groove has forwardly extending leg portions 25shared with adjacent U-shaped grooves on each side thereof so that thecommon leg portions and the bases of the U-shaped grooves provide acontinuous track or cam about the sleeve. When the push button ispressed forwardly into the position shown in Figure 2, the cam rider ispushed along one of the diametrically opposite legs 25 of the U-shapedgrooves. When the button -is'-in-the fully released position illustratedin Figure 1, the cam pin is seated in one of the groove extensions 26which extend rearwardly from the bases of a pair of -U-shaped grooves ondiametrically opposite sides of sleeve 18.

As illustrated most clearly in Figures 1 and 3, the cylindrical sleeve18 is provided with a series of eight parallel and longitudinallyextending passages 27 equally spaced from each other at a uniformdistance from the longitudinal axis of the rotatable shaft 15. Extendingforwardly into the shaft portion 12 of the knob is another set of eightpassages 28 in longitudinal alignment with the sleeve passages 27. Thesetwo sets of passages, one in the cylindrical sleeve 18 and the other inknob 10, combine to form eight elongated passages opening into the innerchamber 11 of the knob.

A tumbler pin 29 is slidably mounted within each of the-combinedpassages of the knob and sleeve and is composed of two separate parts-21front locking pin 30 and a rear setting pin 31. Within each of the knobpassages 28 is a helical tumbler spring 32 which biases each of thetumbler pins rearwardly toward push button 19. Normally, as indicated inFigure l, the locking pins 3% are maintained by springs 32 so thatportions of these pins project into both of the passages 27 and 28 inthe sleeve and knob, respectively. In other words, when the push buttonis in the released position illustrated, the locking pins 30 straddlethe division at 33 between the sleeve and the knob and prevent rotationof that sleeve and shaft 15.

Projecting forwardly into chamber 11 from the rear wall of push button19 are a pair of push pins 34. These push pins are mounted upon button19 at an equal distance from the longitudinal axis of shaft 15, and areparallel to that axis. As the push button is pressed forwardly, and ascam pin 24 is carried into the leg 25 of one of the U-shaped camgrooves, the push button is rotated to bring the push pins 34 intolongitudinal alignment with a pair of diametrically opposite pintumblers 29. Upon further forward movement of the push button, the pushpins are directed into a pair of opposite passages 27 of the sleeve, andinto engagement with the setting pins 31. A pair of locking pins 30 arethereby driven forwardly until they are entirely within the longitudinalpassages 28 of the knob, as indicated in Figure 2. In this manner, apair of locking pins are moved to an unlocking or releasing positionwhere they can no longer interfere with the rotation of shaft and sleeve18 within knob 10.

If the locking pins 30 are driven too far within the passages 28 of theknob, then the setting pins 31 following directly behind the lockingpins will project into passages 28 and will prevent rotation of thecylinder 18 with respect to the knob 10. To unlock the mechanism, it istherefore important that the tumblers 29 be inserted only .far enough tobring the division between each locking pin and the setting pin directlybehind that locking pin into alignment with the division between thecylindrical sleeve 18 and knob 10 indicated by the numeral 33 in Figure2.

So that the two-piece tumbler pins may be temporarily secured inforwardly shifted positions, I provide holding means comprising foursprings 35 carried within a groove 36 extending circumferentially aboutthe cylindrical sleeve 18 and communicating with the plurality oflongitudinal tumbler passages in that sleeve. As most clearly shown inFigure 3, these springs are arranged so that each of their centersections press against two of the pin tumblers 29, and each of theirouter ends are confined by the in- :ncr surface of the push buttoncollar 28.

Upon the inner surface of the collar and adjacent the front end thereofis a wedge-shaped annular relief 37. When the push button is in thenormal position shown in Figure l, the outer ends of the springs seatwithin the annular relief of the push button collar, thereby relievingtension in these springs. As the push button is urged forwardly,however, the rearwardly and inwardly sloping wall of the friction springrelief wedges the friction springs against setting pins 31 so that thesetting and locking pins are held in their forwardly advanced positions.

Although all of the composite tumbler pins are of uniform length, thesetumbler pins are preferably arranged in pairs having component parts ofdifferent lengths. That is, the length of the locking and setting pinsmay vary between different pairs of tumblers. Therefore, the distanceeach pair of tumbler pins must be advanced to retract the locking pins30 completely within the passages 28 of the knob may differ for eachpair of opposing tumbler pins. To indicate the distance each pair oftumbler pins has been advanced, I equip push button 19 with a recess 38which receives a compression spring 39 and a ball 40. A series of ridges41 encircle the inner surface of the knob so that as the push button ispressed forward, the springloaded ball rides over these ridges andproduces pulses which may be sensed by one operating the lock.

The forward end of shaft 15 is equipped with a forwardly extending,eccentric arm 42 which projects into a hole 43 of knob bolt 44. The knobbolt, shown best in Figures 1, 2 and 4, comprises a rod having agenerally square cross section which is slidable transversely through anopening 45 in knob 10. As the shaft 15 is turned, the eccentric arm 42guides the bolt 44 to either a retracted position within opening 45 orto an extended position, as illustrated in Figure 4. A helical spring 46having one of its ends mounted upon sleeve 13 and the other end thereoffastened or hooked upon a connecting bar 47 welded or otherwise securedto the knob 10, biases the rotatable sleeve 18 and shaft 15 so that theknob bolt 44 is normally in an extended position and passages 27 and 28are in horizontal alignment.

The illustrated embodiment of my invention may be operated in thefollowing manner: When the mechanism is locked, knob 10 cannot be turnedbecause knob bolt 44 in its normally extended position latches against asuitable abutment member provided by a door (not shown). To retract theknob bolt and unlock the door, an operator must push button 19 forwardlya total of four times in order to shift the eight locking pins 30 intoreleasing positions. When the push button is pressed the first time, ittravels forwardly within chamber 11 of the knob casing 10 until carnrider 24 is withdrawn from one of the rear extensions 26 of the camgroove 23 on opposite sides of the cylindrical sleeve 18. As the pushbutton continues forwardly, the cam rider is guided along the U-shapedgrooves and rotates the push button one-sixteenth'of a turn in acounterclockwise direction. The two push pins 34 of the button 19 aretherefore brought into longitudinal alignment with a pair of oppositelydisposed two-piece tumbler pins 29.

During the remaining forward displacement of the push button, the camrider is carried into a forwardly extending cam leg 25, and the twotumbler pins are shoved forwardly within passages 27 and 28. As thesetumblers are shifted, the outwardly biased detent or rider 40 engagesridges 41 and produces successive pulses which may be felt by theoperator of the lock as the push button is pressed forwardly. Since thelocking mechanism may be properly positioned by an operators sense oftouch, it is apparent that the locking device of the present inventionmay be operated in complete darkness. Preferably, the pulses emitted areinaudible and may be sensed only by the person operating push button 19.Consequently, the present lock, unlike other combination locks, may beoperated in the presence of other persons without exposing the propercombination settings. While I provide a detent mechanism which producesinaudible pulses, it will of course be apparent that the struc ure ofthismechanismm y be var e or e au ibl signals or clicks are emitted asthe button is depressed,

if such audible signals are considered desirable for any particularapplication of my combination lock.

After the first pair of locking pins have been moved to an unlockingposition, the rearwardly biased push button is released and isautomatically cammed another one-sixteenth of a turn counterclockwise.The tumbler pins which have already been set do not return to theiroriginal position because they are held 'in their forward position byfriction springs 35. Push button 19 is then pressed at second time, andis cammed counterclockwise to bring the paired push pins 34 into contactwith the next set of tumbler pins. The operation described above isrepeated until all four pairs of locking pins have been shoved into thelongitudinal passages of knob 10. The number of pulses produced as thefour pairs or sets of locking pins are driven into the knob passages 28provide the four numbers of the locks operating combination. Hence, ifthe combination of the lock is 5-42-2, then the locking mechanism wouldbe operated so that five pulses are produced when the push button ispressed forwardly the first time, four pulses the second time, and twopulses for each of the third and fourth times the button is depressed.

After the fourth push and before releasing the push button 19 is turnedclockwise about 90". Since all of the locking pins 30 are in releasingpositions, the cylindrical sleeve 18 and shaft 15 are turned, and theeccentric arm 43 withdraws bolt 44 from the locking recess of the door(not shown) into the shaft portion 12 of the knob. The doorknob may thenbe turned'to open the door in the customary manner. When the push buttonis released, shaft 15 is biased by spring 46 back to its original normalposition. Helical spring 46 also rotates push button 19 and compressionspring 21 drives the button rearwardly into the normal position shown inFigure 1. Friction springs 35 are released and tumbler springs 32 directthe locking pins 30 back into the locking positions shown. The lockingmechanism is therefore reset.

While I have described my invention in detail as a doorknob lock, I wishit to be understood that my locking mechanism may be used in connectionwith other locking structures such as padlocks, or with switches such asthe ignition switches of automobiles. The first member which isrepresented in the illustrated embodiment as knob casing might be anysuitable lock or switch casing. The cylindrical sleeve 18 and shaftconstitute a second member which is rotatable with respect to the firstmember. Both the first and second members are equipped with a pluralityof passages 28 and 27 which are normally in longitudinal alignment andare provided with locking pins 30 therein. The locking pins are biasedinto locking positions so that normally the opposite end portions ofeach pin extend within passages of the first and second members, andprevent relative rotation of those members. An unlocking member, thepush button 19, is rotatable along the same axis as the first and secondmembers and is also movable along thelongitudinal axes of the lockingpins. The push button is provided with at least one push pin or finger34 for shoving the locking pins longitudinally within the passages andinto releasing positions wherein these pins reside wholly within thepassages of the first member. Guiding means, which have been describedas cam 23 and cam rider 24, direct the rotational movement of the pushbutton so that one or more of the locking pins are moved to releasedposition each time the push button is moved toward the passages of thefirst and second members. As the push button is advanced and moves thelocking pins into releasing positions, indicating means such as the balldetent and ridges 41 indicate or register the distance advanced by thebutton. Finally, when all of the locking pins have been directed intoreleasing position by successively advancing and retracting the pushbutton, the second member is unlocked or released forrotational-movement with respect to the first member.

While I have described the structure and operation of the push buttondoorknob lock of the present invention in considerable detail forpurposes of illustration, it will be understood that many of thesedetails may be varied considerably without departing from the spirit andprinciples of my invention.

I claim:

1. A combination lock comprising a first member, a second memberrotatably mounted with respect to said first member, said first andsecond members each having a plurality of parallel passages therein, thepassages of said first and second members being normally in longitudinalalignment, a plurality of locking pins each being movable within apassage of said first member and within a corresponding aligned passageof said second member, said pins being movable to a locking positionwherein portions of each of said pins extend within correspondingpassages of said first and second members and also being movable to areleasing position wherein said pins are wholly within the passages ofsaid first member, biasing means provided by said first member forbiasing each of said pins into a locking position, an unlocking memberhaving at least one finger portion projecting towards said secondmember, said unlocking member being movably mounted along thelongitudinal axes of said pins for movement of said finger portiontowards and away from said pins, said unlocking member also beingrotatably mounted with respect to said first and second members foraligning said finger portion with each of said passages and said lockingpins, and means for integrating the rotational and longitudinal movementof said unlocking member so that each of said pins may be shifted into areleasing position by the finger of said unlocking member, whereby saidsecond member may be rotated with respect to said first member when allof said locking pins have been shifted to releasing positions.

2. The structure of claim 1 in which said integrating means comprises acam provided by said second member and a cam rider carried by saidunlocking member.

3. The structure of claim 1 in which said second member is equipped withfriction spring means for maintaining said pins in releasing positionswhile said second member is being rotated with respect to said firstmember.

4. The structure of claim 1 in which said first member is provided witha plurality of transverse ridges and said unlocking member is equippedwith a ball detent adapted to engage said ridges as said unlockingmember is moved longitudinally with respect to said locking pins.

5. A combination lock comprising a casing having a chamber therein, arotatable member mounted within said casing, said casing and rotatablemember each having a plurality of parallel passages therein, thepassages of said rotatable member being in longitudinal alignment withthe passages of said casing, a plurality of locking pins shiftablymounted within the passages of said casing and rotatable member, biasingmeans for biasing said pins into a locking position wherein said pinsconnect the passages of said casing and rotatable member and preventindependent rotation of said member, and a push button being movablelongitudinally toward and away from said member and also being rotatablewith respect to said member, said push button being equipped with atleast one push pin extending toward said rotatable member and beinginsertable within said passages as said push button is moved toward saidmember for shifting said locking pins to releasing positions whereinsaid pins are wholly within the passages of said casing.

6. The structure of claim 5 in which said rotatable member is equippedwith a cam groove and said push button is provided with a cam pinadapted to ride along said groove for directing said push pin into eachof said ayeedeoe passages as'said pusl'i' button advances toward andwithdraws from said rotatable member.

7. A combination doorknob lock comprising a knob casing having anopening therein, a cylindrical member rotatably mounted within saidcasing, said casing and cylindrical member each having a passagetherein, said passages normally being in longitudinal alignment, alocking pin longitudinally movable within said passages, biasing meansfor biasing said pin into a locking position wherein said pin connectssaid passages and prevents independent rotation of said cylindricalmember, and a push button being slidable through the opening of saidcasing and being movable along the longitudinal axis of said pin towardand away from said cylindrical member, said push button being equippedwith a push pin insertable into said passage for shifting said lockingpin into a releasing position wherein said pin is wholly within thepassage of said casing, said push button also being mounted upon saidcylindrical member for rotational movement 'with respect to said knobcasing and being equipped with outer fins for manually rotating saidpush button and said member when said pin is in a releasing position.

8. A combination doorknob lock comprising a knob casing having anopening therein, a cylindrical member rotatably mounted within saidcasing, said casing and cylindrical member each having a plurality ofparallel passages therein, the passages of said cylindrical member beingin longitudinal alignment with the passages of said knob casing, aplurality of locking pins shiftably mounted for longitudinal movementwithin the passages of said casing and cylindrical member, biasing meansfor biasing said pins into locking positions wherein said pins extendthrough both the'pas'sages of said casing and the aligned passages ofsaid cylindrical member and prevent rotation of said member with respectto said casing, and a push button being longitudinally movable throughthe opening of said knob casing toward and away from said cylindricalmember and also being rotatable with respect to said member, said pushbutton being equipped with at least one push pin insertable within saidpassages for shifting said locking pins to releasing positions whereinsaid pins are wholly within the passages of said knob casing.

9. The structure of claim 8 in which said cylindrical member is equippedwith a cam groove about the periphery thereof and said push button isprovided with a cam pin adapted to ride along said groove for rotatingsaid push button and for directing said push pin into longitudinallyaligned passages each time said push button is advanced toward saidcylindrical member.

10. A look comprising a first member, asecond member suppported forrotation with respect thereto, said first and second members each havinga plurality of passages therein arranged in corresponding pairs, saidcor responding passages of said first and second members normally beingin longitudinal alignment, locking pins longitudinally movable withineach pair of aligned passages, biasing means for biasing said pins intolocking position wherein portions of said pins extend wthin each of saidpaired passages and lock said first and second members against relativerotation, an unlocking member being reciprocably movable with respect tosaid first and second members and being equipped with means forconsecutively engaging each of said pins and for shifting saidpins-longitudinally within said passages and into releasing positionswherein said pins are wholly within the passages of said first member,whereby, when all of said locking pins are in said releasing positionssaid second member is released for rotational movement with respect tosaid first member, and friction spring means provided by said secondmember for maintaining said locking pins in releasing positions whensaid second member is being rotated with respect to said first member.

11. The structure of claim 10 in which said first member is providedwith a plurality of ridges extending transversely with respect to thedirection of movement of said unlocking member, and said unlockingmember is equipped with a spring biased rider adapted to successivelyengage said ridges and produce pulses in said unlocking member as saidunlocking member is moved to shift each of said pins from lockingpositions to releasing positions.

12. A look comprising a first member having a plurality of passages, asecond member supported for rotation with reference thereto and having aplurality of passages each alignable with corresponding passages of saidfirst member, the corresponding passages of said first and secondmembers normally being disposed in longitudinal alignment, a pluralityof elongated and transversely divided tumblers each comprising a settingpin and a locking pin, said tumblers being longitudinally slidablewithin said aligned passages, biasing means for urging said tumblersinto locking positions wherein portions of said locking pins extendwithin each of the corresponding passages of said first and secondmembers and lock said members against relative rotation, a reciprocablymovable unlocking member equipped with means for consecutively engagingsaid tumblers and for sliding the same into releasing positions whereinthe division between the locking and setting pins of each tumbler liesbetween said first and second members, whereby, when all of saidtumblers are in releasing positions said second member is released forrotational movement with respect to said first member, said setting pinsof said tumblers being disposed between said locking pins and saidunlocking member, and means for maintaining said tumblers in releasingpositions when the same are being consecutively set and when said secondmember is being rotated with respect to said first member.

13. The structure of claim 12 in which said first member is providedwith a plurality of ridges extending transversely with respect to thedirection of movement of said unlocking member, and said unlockingmember is equipped with a spring-biased rider adapted to successivelyengage said ridges and produce pulses in said unlocking memberas thesame is moved to shift each of said tumblers into a releasing position,thereby enabling an operator to determine upon pushing said unlockingmember when each of said tumblers has reached its preselected releasingposition.

References Cited in the file of this patent UNITED STATES PATENTS240,397 Ehmer Apr. 19, 1881 494,605 Smith Apr. 4, 1893 1,448,888 WaltersMar. 20, 1923 1,500,657 Stolberg July 8, 1924 1,792,949 WeissenboeckFeb. 17, 1931

